Benzylthio pyridazinone derivatives, preparation thereof, and insecticidal acaricidal, fungicidal compositions

ABSTRACT

Novel 3(2H)-pyridazinone derivatives having the formula I: ##STR1## wherein, R is a straight or branched C 2  to C 6  alkyl, R 1  and R 2  are each independently hydrogen or a lower alkyl, R 4  is a halogen, R 3  is a halogen, an alkyl, a cycloalkyl, an alkoxy, a haloalkyl, a haloalkoxy, --CN, --NO 2 , a phenyl, a benzyloxy, a benzyl, a phenoxy, a phenylthio, a pyridyloxy, a quinoxalyloxy, a lower alkenyloxy, a lower alkylthio, a lower haloalkylthio, --Si(CH 3 ) 3 , --OH, --N(CH 3 ) 2 , --SCN, --COOCH 3  or --OCH(CH 3 )COOC 2  H 5 , and n is an integer of 1 to 5, said R 3  being the same or different when n is an integer of 2 to 5. A process for preparation of said derivatives is also provided. These derivatives are useful as an active ingredient of insecticidal, acaricidal, nematicidal and/or fungicidal compositions for agricultural and horticultural uses as well as of expellent compositions for ticks parasitic on animals.

This application is a continuation of application Ser. No. 621,458 filed June 18, 1984, now abandoned.

BACKGROUND OF THE INVENTION

(1) Field of the Invention

This invention relates to novel 3(2H)-pyridazinone derivatives; preparation thereof; insecticidal, acaridical, nematicidal, fungicidal compositions for agricultural and horticultural uses; and expellent compositions for ticks parasitic on animals; said compositions containin said derivatives as an active ingredient.

(2) Description of the Prior Art

Hitherto, there have been reported various 3(2H)-pyridazinone derivatives which have thioether bonding as in the compounds of the present invention. Among them, there have been known the compounds listed in Table 1 below and the physiological activities thereof.

The physiological activities of all the compounds listed in Table 1 are restricted to fungicidal, central nerve depressing- and/or herbicidal actions. It has not been reported at all that these compounds exhibit excellent insecticidal, acaricidal, nematicidal activities which are found in the compounds of the present invention. The compounds according to the present invention have excellent insecticidal, acaricidal and nematicidal activities in addition to fungicidal action. These activities are attributed to the specific structures of the compounds of the present invention. Namely, the compounds of the invention are unique in that they have a straight or branched C₂ to C₆ alkyl group on the 2-position of the pyridazinone ring and also a substituted benzylthio group on the 5-position of said ring. The prior art literature has disclosed neither the compounds of the invention specifically nor physiological activities such as insecticidal, acaricidal, nematicidal activities of the compounds.

                                      TABLE 1                                      __________________________________________________________________________                                       Japanese Patent                                                                Publication No.                              Compound               Physiological activity                                                                    (Publication Date)                           __________________________________________________________________________      ##STR2##              fungicidal action central nerve- depressing                                               09344/67 (5/11/67) 08860/69 (4/24/69)        R: alkyl, benzyl or 4-chlorobenzyl                                              ##STR3##              pressor action                                                                            11902/68 (5/20/68) 11903/68 (5/20/68)                                          11904/68 (5/20/68) 08857/69 (4/24/69)                                          08859/69 (4/24/69) 12421/69 (6/5/69)         R: hydrogen or a halogen                                                       X: a halogen or thiol                                                           ##STR4##               pressor action central nerve- depressing action                               antifungal action                                                                         11905/68 (5/20/68) 11908/68 (5/20/68)        R: phenyl, furyl or thienyl                                                    R.sup.1 : a lower alkyl                                                         ##STR5##              antifungal action                                                                         08860/69 (4/24/69) 08861/69 (4/24/69)        R: a halogen or a lower alkylthio                                               ##STR6##              pressor action antifungal action anti-acetyl                                   choline action                                                                            01302/67 (1/23/67) 11904/68 (5/20/68)                                          11906/68 (5/20/68) 11907/68 (5/20/68)                                          11909/68 (5/20/68) 08858/69 (4/24/68)        R: phenyl, chlorine-substituted phenyl,                                        pyridyl, furyl or thienyl                                                       ##STR7##              antifungal action                                                                         02459/66 (2/17/66) 02788/66 (2/21/66)        X: O or S                                                                       ##STR8##              fungicidal action                                                                         Chemical Abstracts 93, 114552g               R: hydrogen, methyl, ethyl or benzyl                                            ##STR9##              fungicidal action                                                                         Chemical Abstracts 91, 20533h and                                              74637p                                        ##STR10##                                                                     R: hydrogen, an alkyl, phenyl or a halophenyl                                   ##STR11##             herbicidal action                                                                         Japanese Patent  Publication No. No.                                           03798/65                                     R: hydrogen or phenyl                                                          R.sup.2 : an alkyl, phenyl, or CH.sub.2 COOH                                   __________________________________________________________________________

All the compounds represented by the general formulae IV through VIII are apparently different from those of the present invention of the formula I given below in that the former compounds have phenyl group at 2-position. On the other hand, the compounds of the general formula IX are also apparently different therefrom in that the 2-position of the former is not substituted. Moreover, the thiol compounds and the salts thereof having the formula X are reported to have fungicidal activity and are different from those of the present invention in that the former have a substituted benzylthio group at 5-position.

The present inventors have conducted intensive research on the preparation of the novel compounds of the formula I given below as well as on activities thereof as an agricultural drug, and have found that the compounds of the formula I are useful for the control of agricultural and horticultural insect pests and acari, for the prevention of blight and for expelling ticks parasitic on animals to accomplish the invention.

SUMMARY OF THE INVENTION

An object of this invention is to provide novel 3(2)-pyridazinone derivatives which have insecticidal, acaricidal bactericidal and nematicidal activities.

Another object of this invention is to provide a process for preparing such 3(2H)-pyridazinone derivatives.

Further object of this invention is to provide bactericidal, insecticidal, acaricidal, nematicidal compositions containing a 3(2H)-pyridazinone derivative as an active ingredient.

Other objects of this invention will become apparent from the description given below.

The 3(2H)-pyridazinone derivatives according to the invention have the general formula (I): ##STR12## wherein, R denotes a straight or branched C₂ to C₆ alkyl, R¹ and R² denote each independently hydrogen or a lower alkyl, R⁴ denotes a halogen, R³ denotes a halogen; a straight or branched C₁ to C₁₂ alkyl, a cycloalkyl unsubstituted or substituted by a lower alkyl; a straight or branched C₁ to C₁₂ alkoxy; a lower haloalkyl; a lower haloalkoxy; ##STR13## (wherein X denotes a halogen, a lower alkyl, a cycloalkyl, a lower alkoxy, a lower haloalkyl, a lower haloalkoxy, --CN or --NO₂ and m denotes 0 or an integer of 1 to 5, said X being the same or different when m is an integer of 2 to 5); a pyridyloxy which may be substituted by a halogen and/or --CF₃ ; a quinoxalyloxy which may be substituted by a halogen and/or --CF₃ ; a lower alkenyloxy; a lower alkylthio; a lower haloalkylthio; --Si(CH₃)₃ ; --OH; --N(CH₃)₂ ; --SCN; --COOCH₃ ; or --OCH(CH₃)COOC₂ H₅, and n denotes an integer of 1 to 5, said R³ being the same or different when n is an integer of 2 to 5.

The present invention also comprises a process for preparation of said derivatives; insecticidal, acaricidal, nematicidal, and/or fungicidal compositions for agricultural and horticultural uses; and compositions for expelling ticks that are parasitic on animals; said compositions containing said derivatives as an active ingredient.

The compounds according to the present invention particularly have high insecticidal and acaricidal activities and exhibit excellent immediate effects and residual activity.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

The "lower alkyl" including the lower alkyl moieties contained in the groups such as "lower alkoxy", "lower haloalkyl", "lower haloalkoxy", "lower alkylthio" and "lower haloalkylthio" are usually a straight or branched alkyl of 1 to 6 carbon atoms, preferably of 1 to 4 carbon atoms such as methyl, ethyl, n-propyl, i-propyl, n-butyl, iso-butyl, sec.-butyl or tert.-butyl.

The "lower alkenyl" contained in the lower alkenyloxy is usually a straight or branched alkenyl of 2 to 6 carbon atoms, preferably of 2 to 4 carbon atoms such as ethenyl, n-propenyl, n-propadienyl, i-propenyl, n-butenyl, n-butadienyl, n-butatrienyl, sec.-butenyl, and sec.-butadienyl.

The term "halogen" and halogens contained in the groups such as "haloalkyl", "haloalkoxy" and "haloalkylthio" mean florine, chlorine, bromine, iodine atom or a mixture thereof.

The "cycloalkyl" as R³ or as a substituent X preferably has 3 to 6 carbon atoms.

R is preferably a straight or branched alkyl of 2 to 4 carbon atoms, such as ethyl, n-propyl, i-propyl, n-butyl, iso-butyl, sec.-butyl, or tert.-butyl, and most preferably tert.-butyl. R¹ and R² are each preferably hydrogen or a straight or branched lower alkyl of 1 to 3 carbon atoms such as methyl, ethyl, n-propyl or i-proyl, and more preferably hydrogen, methyl or ethyl.

R³ is preferably a straight or branched alkyl of C₃ to C₈, (such as i-propyl, t-butyl, i-tubyl, n-hexyl, n-heptyl, n-octyl), C₂ to C₈ alkoxyl (such as ethoxy, n-propoxy, i-propoxy, n-pentyloxy, n-hexyloxy, n-heptyloxy). Further R³ is preferably phenyl, ##STR14## --OCHF₂, cyclopropyl, cyclohexyl, allyloxy, 2-butenyloxy and --Si(CH₃)₃. Most preferably R³ is t-butyl, phenyl, cyclohexyl and ##STR15## The preferable position of R³ is 4-position.

R⁴ is preferably chlorine or bromine, more preferably chlorine.

n is preferably an integer of 1 to 3, more preferably 1 or 2, and most preferably 1.

The following compounds are most important from the viewpoint of pesticidal activities:

    __________________________________________________________________________     Compound No.                                                                   __________________________________________________________________________     70.     2-tert.-butyl-4-chloro-5-(4-tert.-butyl-α-methyl-                        benzylthio)-3(2H)pyridazinone                                                   ##STR16##                                                             81.     2-tert.-butyl-4-chloro-5-(4-tert.-butyl-                                       benzylthio-3(2H)pyridazinone                                                    ##STR17##                                                             88.     2-tert.-butyl-4-chloro-5-(4-cyclohexyl-                                        benzylthio)-3(2H)pyridazinone                                                   ##STR18##                                                             95.     2-tert.-butyl-4-chloro-5-(4-phenyl-benzyl-                                     thio)-3(2H)pyridazinone                                                         ##STR19##                                                             103.    2-tert.-butyl-4-chloro-5-(4-iso-propyl-α-                                methylbenzylthio)-3(2H)pyridazinone                                             ##STR20##                                                             106.    2-tert.-butyl-4-chloro-5-(4-cyclohexyl-α-                                methylbenzylthio)-3(2H)pyridazinone                                             ##STR21##                                                             109.    2-tert.-butyl-4-chloro-5-(4-phenyl-α-methyl-                             benzylthio)-3(2H)pyridazinone                                                   ##STR22##                                                             129.    2-tert.-butyl-4-chloro-5-(4-allyloxy-                                          benzylthio)-3(2H)pyridazinone                                                   ##STR23##                                                             133.    2-tert.-butyl-4-chloro-5-(4-trimethylsilyl-                                    benzylthio)-3(2H)pyridazinone                                                   ##STR24##                                                             138.    2-tert.-butyl-4-chloro-5-(4-difluoromethoxy-                                   benzylthio)-3(2H)pyridazinone                                                   ##STR25##                                                             141.    2-tert.-butyl-4-chloro-5-(4-cyclopropyl-                                       benzylthio)-3(2H)pyridazinone                                                   ##STR26##                                                             153.    2-tert.-butyl-4-chloro-5-(4-ethoxy-                                            benzylthio)-3(2H)pyridazinone                                                   ##STR27##                                                             154.    2-tert.-butyl-4-chloro-5-(4-n-propoxy-                                         benzylthio)-3(2H)pyridazinone                                                   ##STR28##                                                             155.    2-tert.-butyl-4-chloro-5-(4-iso-butyl-benzylthio)-                             3(2H)pyridazinone                                                               ##STR29##                                                             157.    2-tert.-butyl-4-chloro-5-(4-n-hexyl-benzylthio)-                               3(2H)pyridazinone                                                               ##STR30##                                                             158.    2-tert.-butyl-4-chloro-5-(4-n-heptyl-benzylthio)-                              3(2H)pyridazinone                                                               ##STR31##                                                             159.    2-tert.-butyl-4-chloro-5-(4-n-octyl-benzylthio)-                               3(2H)pyridazinone                                                               ##STR32##                                                             163.    2-tert.-butyl-4-chloro-5-(4-iso-propoxy-benzylthio)-                           3(2H)pyridazinone                                                               ##STR33##                                                             169.    2-tert.-butyl-4-chloro-5-(4-n-pentyloxy-benzylthio)-                           3(2H)pyridazinone                                                               ##STR34##                                                             170.    2-tert.-butyl-4-chloro-5-(4-n-hexyloxy-benzylthio)-                            3(2H)pyridazinone                                                               ##STR35##                                                             171.    2-tert.-butyl-4-chloro-5-(4-n-heptyloxy-benzylthio)-                           3(2H)pyridazinone                                                               ##STR36##                                                             180.    2-tert.-butyl-4-chloro-5-[4-(2-butenyloxy)-                                    benzylthio]-3(2H)pyridazinone                                                   ##STR37##                                                             243.    2-tert.-butyl-4-chloro-5-[4-(4-trifluoromethyl-                                phenoxy)-benzylthio]-3(2H)pyridazinone                                          ##STR38##                                                             245.    2-tert.-butyl-4-chloro-5-[4-(4-tert.-butyl-                                    phenoxy)-α-methylbenzylthio]-3(2H)pyridazinone                            ##STR39##                                                             __________________________________________________________________________

More preferable compounds are those of Compound Nos. 70, 81, 88, 95, 106, 109 and 243.

The compounds listed in Table 2 below are exemplified as the compounds to be included in the present invention. However, it should be understood that the compounds in Table 2 are only illustrative and not to restrict the invention. Incidentally, a compound of the invention containing asymmetric carbon atom(s) includes optically active (+) compound and (-) compound.

                  TABLE 2                                                          ______________________________________                                         Compounds of the formula I:                                                     ##STR40##                    (I)                                              [In Table 2, "Me" denotes methyl, "Et" denotes ethyl, "Pr"                     denotes propyl, "Bu" denotes butyl, "Pen" denotes pentyl,                      "Hex" denotes hexyl, "n" denotes normal, "t" denotes tertiary,                 "i" denotes iso, and "s" denotes secondary.]                                   No.  R       R.sup.1                                                                               R.sup.2                                                                             R.sup.4                                                                            R.sup.3 n                                         ______________________________________                                         1    Et      H      H    Cl  4-t-Bu                                            2    Et      H      H    Cl  4-F                                               3    Et      H      H    Cl  3-CF.sub.3                                        4    Et      H      H    Cl                                                                                  ##STR41##                                        5    Et      H      H    Cl                                                                                  ##STR42##                                        6    Et      H      H    Cl                                                                                  ##STR43##                                        7    Et      Me     H    Cl  4-OCF.sub.2 CF.sub.3                              8    Et      Me     Me   Cl  4-t-Bu                                            9    Et      H      H    Br                                                                                  ##STR44##                                        10   Et      H      H    Br  4-CF.sub.3                                        11   Et      H      H    Br  2,3,4,5,6-F.sub.5                                 12   Et      Me     H    Br  4-t-Bu                                            13   Et      Me     H    Br  4-F                                               14   n-Pr    H      H    Cl  4-t-Bu                                            15   n-Pr    H      H    Cl                                                                                  ##STR45##                                        16   n-Pr    H      H    Cl                                                                                  ##STR46##                                        17   n-Pr    H      H    Cl  4-F                                               18   n-Pr    H      H    Cl  2,4-Cl.sub.2                                      19   n-Pr    Me     H    Cl  4-t-Bu                                            20   n-Pr    Me     H    Cl                                                                                  ##STR47##                                        21   n-Pr    Me     H    Cl  2,4-Cl.sub.2                                      22   n-Pr    H      H    Cl  3,5-Cl.sub.2                                      23   n-Pr    H      H    Cl  3-CN                                              24   n-Pr    Me     H    Cl  4-i-Pr                                            25   n-Pr    Me     H    Cl  4-Cl                                              26   n-Pr    Me     Me   Cl  4-t-Bu                                            27   n-Pr    H      H    Br  2-OCF.sub.3                                       28   n-Pr    H      H    Br                                                                                  ##STR48##                                        29   i-Pr    H      H    Cl  3,4-Cl.sub.2                                      30   i-Pr    H      H    Cl  4-t-Bu                                            31   i-Pr    H      H    Cl  2-NO.sub.2                                        32   i-Pr    H      H    Cl  4-OEt                                             33   i-Pr    Et     Me   Cl  3-Br                                              34   i-Pr    n-Pr   H    Cl  4-Me                                              35   i-Pr    H      H    Br  2-OMe                                             36   i-Pr    H      H    Br  3-CF.sub.3                                        37   i-Pr    Me     H    Br  4-F                                               38   i-Pr    Me     Me   Br                                                                                  ##STR49##                                        39   n-Bu    H      H    Cl  4-Br                                              40   n-Bu    H      H    Cl  3,4-Cl.sub.2                                      41   n-Bu    H      H    Cl  2-CF.sub.3                                        42   n-Bu    H      H    Cl  3-OCH.sub.2 CF.sub.3                              43   n-Bu    Me     H    Cl                                                                                  ##STR50##                                        44   n-Bu    n-Bu   H    Cl                                                                                  ##STR51##                                        45   n-Bu    Et     Et   Cl                                                                                  ##STR52##                                        46   n-Bu    H      H    Br  3-OCF.sub.3                                       47   n-Bu    H      H    Br                                                                                  ##STR53##                                        48   n-Bu    H      H    Br  2,4-Cl.sub.2                                      49   i-Bu    H      H    Cl  3-Me                                              50   i-Bu    H      H    Cl  3,4-(Me).sub.2                                    51   i-Bu    H      H    Cl                                                                                  ##STR54##                                        52   i-Bu    H      H    Cl  2-Cl, 4-Me                                        53   i-Bu    Me     H    Cl  2-Cl, 4-F                                         54   i-Bu    Et     H    Cl  2,6-Cl.sub.2                                      55   i-Bu    Et     Me   Br  4-Cl                                              56   s-Bu    H      H    Cl  2-Cl, 4-F                                         57   s-Bu    H      H    Cl  2-Me, 4-Cl                                        58   s-Bu    H      H    Cl                                                                                  ##STR55##                                        59   s-Bu    H      H    Cl  4-t-Bu                                            60   s-Bu    H      H    Cl  2,5-(Me).sub.2                                    61   s-Bu    Me     H    Cl  4-F                                               62   s-Bu    Et     H    Cl  4-F                                               63   s-Bu    H      H    Cl                                                                                  ##STR56##                                        64   s-Bu    H      H    Br                                                                                  ##STR57##                                        65   s-Bu    H      H    Br  4-CN                                              66   s-Bu    H      H    Br  3-CF.sub.3                                        67   s-Bu    H      H    Br  2-F, 4-CF.sub.3                                   68   s-Bu    Me     H    Br  2-F, 4-Cl                                         69   s-Bu    i-Pr   H    Br  4-OCF.sub.3                                       70   t-Bu    Me     H    Cl  4-t-Bu                                            71   optically active compound (+) of Compound No. 70                          72   optically active compound (-) of Compound No. 70                          73   t-Bu    H      H    Cl                                                                                  ##STR58##                                        74   t-Bu    H      H    Cl                                                                                  ##STR59##                                        75   t-Bu    H      H    Cl                                                                                  ##STR60##                                        76   t-Bu    H      H    Cl                                                                                  ##STR61##                                        77   t-Bu    H      H    Cl  2-Me                                              78   t-Bu    H      H    Cl  3-Me                                              79   t-Bu    H      H    Cl  4-Me                                              80   t-Bu    H      H    Cl  4-i-Pr                                            81   t-Bu    H      H    Cl  4-t-Bu                                            82   t-Bu    H      H    Cl  2-Cl                                              83   t-Bu    H      H    Cl  2,4-Cl.sub.2                                      84   t-Bu    H      H    Cl  3,4-Cl.sub.2                                      85   t-Bu    H      H    Cl  2-Cl, 4-Me                                        86   t-Bu    H      H    Cl  2-F, 4-Cl                                         87   t-Bu    H      H    Cl  4-F                                               88   t-Bu    H      H    Cl                                                                                  ##STR62##                                        89   t-Bu    H      H    Cl                                                                                  ##STR63##                                        90   t-Bu    H      H    Cl  3-CF.sub.3                                        91   t-Bu    H      H    Cl  3-OMe                                             92   t-Bu    H      H    Cl  4-OCF.sub.3                                       93   t-Bu    H      H    Cl  2-OCF.sub.3, 4-Cl                                 94   t-Bu    H      H    Cl  2,3,4,5,6-F.sub.5                                 95   t-Bu    H      H    Cl                                                                                  ##STR64##                                        96   t-Bu    H      H    Cl                                                                                  ##STR65##                                        97   t-Bu    H      H    Cl  4-Br                                              98   t-Bu    H      H    Cl                                                                                  ##STR66##                                        99   t-Bu    H      H    Cl                                                                                  ##STR67##                                        100  t-Bu    H      H    Cl                                                                                  ##STR68##                                        101  t-Bu    Me     H    Cl  3-Me                                              102  t-Bu    Me     H    Cl  4-Me                                              103  t-Bu    Me     H    Cl  4-i-Pr                                            104  t-Bu    H      H    Cl                                                                                  ##STR69##                                        105  t-Bu    Me     H    Cl                                                                                  ##STR70##                                        106  t-Bu    Me     H    Cl                                                                                  ##STR71##                                        107  t-Bu    Me     H    Cl  4-Br                                              108  t-Bu    Me     H    Cl  4-Cl                                              109  t-Bu    Me     H    Cl                                                                                  ##STR72##                                        110  t-Bu    Et     H    Cl  4-t-Bu                                            111  t-Bu    Me     Me   Cl                                                                                  ##STR73##                                        112  t-Bu    H      H    Cl  2-NO.sub.2                                        113  t-Bu    H      H    Br  4-Me                                              114  t-Bu    H      H    Br  4-F                                               115  t-Bu    Et     H    Cl  4-Cl                                              116  t-Bu    H      H    Br  4-CF.sub.3                                        117  t-Bu    H      H    Br  2-OCH.sub.2 CF.sub.3                              118  t-Bu    H      H    Br  4-OCF.sub.3                                       119  t-Bu    H      H    Br  4-CN                                              120  t-Bu    H      H    Br  3-NO.sub.2                                        121  t-Bu    H      H    Br                                                                                  ##STR74##                                        122  t-Bu    H      H    Br                                                                                  ##STR75##                                        123  t-Bu    Me     H    Br  2-F                                               124  t-Bu    Me     H    Br                                                                                  ##STR76##                                        125  t-Bu    n-Pr   Me   Br                                                                                  ##STR77##                                        126  t-Bu    H      H    Cl                                                                                  ##STR78##                                        127  t-Bu    H      H    Cl                                                                                  ##STR79##                                        128  t-Bu    H      H    Cl                                                                                  ##STR80##                                        129  t-Bu    H      H    Cl  4-OCH.sub.2 CHCH.sub.2                            130  t-Bu    H      H    Cl  4-SC.sub.4 H.sub.9n                               131  t-Bu    H      H    Cl  4-SMe                                             132  t-Bu    H      H    Cl  3-OC.sub.4 H.sub.9n                               133  t-Bu    H      H    Cl  4-Si(Me).sub.3                                    134  t-Bu    Me     H    Cl                                                                                  ##STR81##                                        135  t-Bu    Me     H    Cl                                                                                  ##STR82##                                        136  t-Bu    H      H    Cl  4-SCHF.sub.2                                      137  t-Bu    H      H    Cl  4-OCH.sub.2 CH.sub.2 CH.sub.2 Cl                  138  t-Bu    H      H    Cl  4-OCHF.sub.2                                      139  t-Bu    H      H    Br  4-t-Bu                                            140  t-Bu    H      H    Br  4-Cl                                              141  t-Bu    H      H    Cl                                                                                  ##STR83##                                        142  t-Bu    H      H    Cl  4-C(Me).sub.2 CH.sub.2 Cl                         143  t-Bu    H      H    Cl  4-OCHC(Me)CH.sub.2                                144  t-Bu    H      H    Cl  3,5-(t-Bu).sub.2, 4-OH                            145  t-Bu    H      H    Cl  3,5-(Br).sub.2, 4-OH                              146  t-Bu    H      H    Br                                                                                  ##STR84##                                        147  t-Bu    H      H    Br  4-n-Bu                                            148  t-Bu    H      H    Br  4-OC.sub.6 H.sub.13n                              149  t-Bu    Me     H    Br                                                                                  ##STR85##                                        150  t-Bu    H      H    Cl  4-N(Me).sub.2                                     151  t-Bu    H      H    Cl  3-OMe, 4-OPri                                     152  t-Bu    H      H    Cl  4-I                                               153  t-Bu    H      H    Cl  4-OEt                                             154  t-Bu    H      H    Cl  4-OPrn                                            155  t-Bu    H      H    Cl  4-i-Bu                                            156  t-Bu    H      H    Cl  4-n-Bu                                            157  t-Bu    H      H    Cl  4-n-C.sub.6 H.sub.13                              158  t-Bu    H      H    Cl  4-n-C.sub.7 H.sub.15                              159  t-Bu    H      H    Cl  4-n-C.sub.8 H.sub.17                              160  t-Bu    H      H    Cl  4-s-Bu                                            161  t-Bu    H      H    Cl  4-t-C.sub.5 H.sub.11                              162  t-Bu    H      H    Cl  4-COOMe                                           163  t-Bu    H      H    Cl  4-OPri                                            164  t-Bu    H      H    Cl  4-OCH.sub.2 CH(Et)Bun                             165  t-Bu    H      H    Cl  4-OC.sub.9 H.sub.19 n                             166  t-Bu    H      H    Cl  4-OC.sub.11 H.sub.23 n                            167  t-Bu    Me     H    Cl  4-OC.sub.10 H.sub.21 n                            168  t-Bu    H      H    Cl  4-OC.sub.4 H.sub.9 n                              169  t-Bu    H      H    Cl  4-OC.sub.5 H.sub.11 n                             170  t-Bu    H      H    Cl  4-OC.sub.6 H.sub.13 n                             171  t-Bu    H      H    Cl  4-OC.sub.7 H.sub.15 n                             172  t-Bu    H      H    Cl  4-OC.sub.8 H.sub.17 n                             173  t-Bu    H      H    Cl  2,6-(Me).sub.2, 4-t-Bu                            174  t-Bu    H      H    Cl  3,5-Br.sub.2, 4-OPri                              175  t-Bu    H      H    Cl  4-Cl                                              176  t-Bu    H      H    Cl  4-CF.sub.3                                        177  t-Bu    H      H    Cl                                                                                  ##STR86##                                        178  t-Bu    H      H    Cl                                                                                  ##STR87##                                        179  t-Bu    H      H    Cl  4-OCH(Me)COOEt                                    180  t-Bu    H      H    Cl  4-OCH.sub.2 CHCHMe                                181  t-Bu    H      H    Cl  4-SCN                                             182  n-Pen   H      H    Cl  4-Cl                                              183  n-Pen   H      H    Cl  3-Me                                              184  n-Pen   H      H    Cl                                                                                  ##STR88##                                        185  n-Pen   Me     H    Cl  4-CN                                              186  n-Pen   Et     H    Cl  3-CF.sub.3                                        187  n-Pen   Et     Et   Cl                                                                                  ##STR89##                                        188  n-Pen   H      H    Br                                                                                  ##STR90##                                        189  n-Pen   H      H    Br  2-Cl, 4-Me                                        190  n-Pen   Me     H    Br  2-Me, 4-Cl                                        191  i-Pen   H      H    Cl  4-Br                                              192  i-Pen   H      H    Cl  4-NO.sub.2                                        193  i-Pen   H      H    Cl                                                                                  ##STR91##                                        194  i-Pen   H      H    Cl                                                                                  ##STR92##                                        195  i-Pen   Me     H    Cl                                                                                  ##STR93##                                        196  i-Pen   Et     H    Br  3-OCF.sub.2 CF.sub.3                              197  n-Hex   H      H    Cl  2-F                                               198  n-Hex   H      H    Cl  4-Et                                              199  n-Hex   H      H    Cl                                                                                  ##STR94##                                        200  n-Hex   H      H    Cl                                                                                  ##STR95##                                        201  n-Hex   H      H    Cl                                                                                  ##STR96##                                        202  n-Hex   Me     H    Cl  4-CN                                              203  n-Hex   Me     H    Cl  2-NO.sub.2                                        204  n-Hex   Et     Me   Cl  4-F                                               205  n-Hex   Et     Me   Cl                                                                                  ##STR97##                                        206  n-Hex   H      H    Br  4-CF.sub.3                                        207  n-Hex   H      H    Br  3-OCF.sub.3                                       208  n-Hex   H      H    Br                                                                                  ##STR98##                                        209  n-Hex   Me     H    Br                                                                                  ##STR99##                                        210  n-Hex   Me     H    Br  3-OCF.sub.3                                       211  n-Hex   Me     H    Br  4-Cl                                              212  n-Hex   Et     H    Br  2-Me                                              213  n-Hex   Et     Me   Br  2,4-(Me).sub.2                                    214  n-Hex   Et     Et   Br  3,4-Cl.sub.2                                      215  n-Hex   Et     Et   Br                                                                                  ##STR100##                                       216  Et      H      H    Cl                                                                                  ##STR101##                                       217  Et      H      H    Cl                                                                                  ##STR102##                                       218  Et      H      H    Cl                                                                                  ##STR103##                                       219  Et      H      H    Cl                                                                                  ##STR104##                                       220  Et      Et     Me   Br                                                                                  ##STR105##                                       221  i-Pr    H      H    Br                                                                                  ##STR106##                                       222  i-Pr    Me     Me   Br                                                                                  ##STR107##                                       223  i-Pr    H      H    Cl                                                                                  ##STR108##                                       224  i-Pr    H      H    Cl                                                                                  ##STR109##                                       225  i-Pr    Me     H    Cl                                                                                  ##STR110##                                       226  n-Pr    Me     H    Br                                                                                  ##STR111##                                       227  n-Pr    H      H    Cl                                                                                  ##STR112##                                       228  n-Pr    Et     H    Cl                                                                                  ##STR113##                                       229  i-Bu    n-Pr   H    Br                                                                                  ##STR114##                                       230  i-Bu    Me     H    Br                                                                                  ##STR115##                                       231  n-Bu    H      H    Br                                                                                  ##STR116##                                       232  n-Bu    H      H    Cl                                                                                  ##STR117##                                       233  n-Bu    H      H    Cl                                                                                  ##STR118##                                       234  n-Bu    H      H    Cl                                                                                  ##STR119##                                       235  s-Bu    H      H    Cl                                                                                  ##STR120##                                       236  t-Bu    H      H    Cl                                                                                  ##STR121##                                       237  t-Bu    Me     Me   Br                                                                                  ##STR122##                                       238  t-Bu    H      H    Br                                                                                  ##STR123##                                       239  t-Bu    Et     H    Br                                                                                  ##STR124##                                       240  t-Bu    H      H    Br                                                                                  ##STR125##                                       241  t-Bu    Me     Me   Br                                                                                  ##STR126##                                       242  t-Bu    H      H    Cl                                                                                  ##STR127##                                       243  t-Bu    H      H    Cl                                                                                  ##STR128##                                       244  t-Bu    H      H    Cl                                                                                  ##STR129##                                       245  t-Bu    Me     H    Cl                                                                                  ##STR130##                                       246  t-Bu    H      H    Cl                                                                                  ##STR131##                                       247  t-Bu    H      H    Cl                                                                                  ##STR132##                                       248  t-Bu    H      H    Cl                                                                                  ##STR133##                                       249  t-Bu    H      H    Cl                                                                                  ##STR134##                                       250  i-Pen   H      H    Cl                                                                                  ##STR135##                                       251  i-Pen   H      H    Cl                                                                                  ##STR136##                                       252  i-Pen   Me     H    Cl                                                                                  ##STR137##                                       253  i-Pen   Et     Me   Br                                                                                  ##STR138##                                       254  i-Pen   Me     Me   Cl                                                                                  ##STR139##                                       255  i-Pen   Et     Et   Br                                                                                  ##STR140##                                       256  n-Pen   H      H    Cl                                                                                  ##STR141##                                       257  n-Hex   H      H    Cl                                                                                  ##STR142##                                       258  n-Hex   H      H    Cl                                                                                  ##STR143##                                       259  n-Hex   H      H    Br                                                                                  ##STR144##                                       260  t-Bu    H      H    Cl                                                                                  ##STR145##                                       ______________________________________                                    

The compounds of the formula I can be produced by reacting a compound of the formula IIA: ##STR146## wherein R and R⁴ have the same meanings as defined in formula I, and Y denotes --SH, a halogen or --OR⁵ (wherein R⁵ denotes a lower alkyl) with a compound of the formula IIIA: ##STR147## wherein R¹, R², R³ and n have the same meanings as defined in formula I, and Z denotes a halogen or --SH, provided that Z denotes a halogen when Y is --SH and Z denotes --SH when Y is a halogen or --OR⁵.

Specifically, the compounds of the present invention can be produced according to the following Reaction (1), (2) or (3): ##STR148## wherein R, R¹, R², R³, R⁴ and n in the above Reactions (1) through (3) have the same meanings as defined above, hal denotes a halogen and R⁵ denotes a lower alkyl.

Namely, the compounds of the invention can be produced by reacting a 3(2H)-pyridazinone derivative of the formula II, XVIII or XV as one of the raw materials with a benzyl compound of the formula III or XIV as the other material in an appropriate solvent in the presence of a hydrogen halide-absorbing agent or an alcohol-removing agent.

As the solvent can be used lower alcohols such as methanol, ethanol; ketones such as acetone, methylethyl keton; hydrocarbons such as benzene, toluene; ethers such as isopropyl ether, tetrahydrofuran, 1,4-dioxane; amides such as N,N-dimethylformamide, hexamethyl phosphoric triamide; and halogenated hydrocarbons such as dichloromethane. As necessary, these solvents can be used as a mixture with water.

As the hydrogen halide-absorbing agent can be used inorganic bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate; and organic bases such as triethylamine, pyridine. As necessary, there may be added to the reaction system a catalyst such as tetraammonium salts (e.g. triethylbenzylammonium chloride).

The reaction temperature ranges from room temperature to the boiling point of the solvent to be used in the reaction.

The ratio of the raw materials can be optionally selected. However, it is advantageous to conduct the reaction using equimolar or nearly equimolar amount of the materials.

Incidentally, the compounds of the formula II in the above can be prepared by a process according to the following reaction: ##STR149## wherein, R, R⁴ and Hal have the same meanings as defined above.

Preparation of the compounds I of the invention is described more in detail by way of the following examples which are not to restrict the invention.

SYNTHESIS EXAMPLE 1 Synthesis of 2-tert.-butyl-4-chloro-5-mercapto-3(2H)-pyridazinone

To 560 ml of water were added 66.3 g of 2-tert.-butyl-4,5-dichloro-3(2H)-pyridazinone and 48.0 g of 70% sodium hydrosulfide. After stirring at 60° C. for 4 hours activated carbon was added thereto. The resulting mixture was allowed to cool and then filtered. Concentrated hydrochloric acid was added to the resuling filtrate until the pH thereof was lowered to 2 or less. The resulting solid was filtered off, washed with water, dried and then recrystallized from a mixed solvent of benene and n-hexane to give the intended product as white needle-like crystals of m.p. 112°-113° C. (yield: 81.5%).

The compound thus obtained was analyzed by means of ¹ H-NMR spectrum in deutero chloroform (CDCl₃) to obtain the following results:

¹ H-NMR(CDCl₃), δ(ppm): 1.61(9H, s, 2-t-Bu), 4.04(1H, s, --SH), 7.56(1H, s, 6-H).

SYNTHESIS EXAMPLE 2 Synthesis of 2-tert.-butyl-4-bromo-5-mercapto-3(2H)-pyridazinone

To 200 ml of water were added 31.0 g of 2-tert.-butyl-4,5-dibromo-3(2H)-pyridazinone and 15.8 g of 70% sodium hydrosulfide. After stirring at 60° C. for 4 hours, the resulting mixture was allowed to cool to room temperature and incorporated with about 8 ml of concentrated hydrochloric acid to lower the pH of the liquid to not higher than 2. The resulting solid was filtered off, washed with water, dried and then recrystallized from benzene/n-hexane to give 8.0 g of the intended product as white crystals of m.p. 107°-110° C. (yield: 30.4%).

The compound thus obtained was analyzed by means of ¹ H-NMR spectrum in deutero chloroform (CDCl₃) to obtain the following results:

¹ H-NMR(CDCl₃), δ(ppm): 1.63(9H, s, 2-t-Bu), 4.18(1H, s, --SH), 7.53(1H, s, 6-H).

SYNTHESIS EXAMPLE 3 Synthesis of 2-tert.-butyl-4-chloro-5-(2-methylbenzylthio)-3(2H)-pyridazinone (Compound No. 77) ##STR150##

In 10 ml of N,N-dimethylformamide was dissolved 1.5 g of 2-tert.-butyl-4-chloro-5-mercapto-3(2H)-pyridazinone, and thereto were added 1.2 g of anhydrous potassium carbonate and 1.0 g of α-chloro-o-xylene. The resulting mixture was heated to 80° to 110° C. under stirring for 2 hours. After allowed to cool to room temperature, the mixture was incorporated with 100 ml of water and then stirred. The precipitated solid was filtered off, washed with water, dried and recrystallized from ethanol to give white needle-like crystals having the following physical properties (yield: 72.7%):

mp: 138.0°-139.0° C.

¹ H-NMR(CDCl₃), δ(ppm): 1.62(9H, s, 2-t-Bu), 2.40(3H, s, 2'--CH₃), 4.21(2H, s, --SCH₂ --), 7.18(4H, m, phenyl), 7.61(1H, s, 6-H).

SYNTHESIS EXAMPLE 4 Synthesis of 2-tert.-butyl-4-chloro-5-(4-tert.-butyl-benzylthio)-3(2H)-pyridazinone (Compound No. 81) ##STR151##

By conducting a procedure similar to that in Synthesis Example 3 except using 2.0 g of 2-tert.-butyl-4-chloro-5-mercapto-3(2H)-pyridazinone, 15 ml of N,N-dimethylformamide, 1.3 g of anhydrous sodium carbonate and 1.6 g of 4-tert.-butylbenzyl chloride, there were obtained white needle-like crystals having the following physical properties (yield: 87.9%):

m.p.: 111.0°-112.0° C.

¹ H-NMR(CDCl₃), δ(ppm): 1.29(9H, s, 4'-t-Bu), 1.60(9H, s, 2-t-Bu), 4.21(2H, s, --SCH₂ --), 7.32(4H, m, phenyl), 7.61(1H, s, 6-H).

SYNTHESIS EXAMPLE 5 Synthesis of 2-tert.-butyl-4-chloro-5-(4-tert.-butyl-α-methylbenzylthio)-3(2H)-pyridazinone (Compound No. 70) ##STR152##

By conducting a procedure similar to that in Synthesis Example 3 except using 1.5 g of 2-tert.-butyl-4-chloro-5-mercapto-3(2H)-pyridazinone, 10 ml of N,N-dimethylformamide, 1.0 g of anhydrous sodium carbonte and 1.4 g of 4-tert.-butyl-α-methylbenzyl chloride, there were obtained white needle-like crystals having the following physical properties (yield: 72.7%):

m.p.: 100.0°-106.0° C.

1H-NMR(CDCl₃), δ(ppm): 1.29(9H, s, 4'-t-Bu), 1.58(9H, s, 2-t-Bu), 1.70(3H, d, J=7 Hz, α--CH₃), 4.58(1H, q, --SCH<), 7.33(4H, m, phenyl), 7.56(1H, s, 6-H).

SYNTHESIS EXAMPLE 6 Synthesis of (+)2-tert.-butyl-4-chloro-5-(4-tert.-butyl-α-methylbenzylthio)-3(2H)-pyridazinone (Compound No. 71)

In 300 ml of 0.2M aqueous solution of disodium hydrogenphosphate (pH 9.1) was suspended 17.0 g (77.2 m mol) of p-tert.-butyl-α-methylbenzyl acetate, and 1.00 g of bovin liver acetone powder was added thereto. After stirring at room temperature for 77 hours, the reaction liquid was extracted twice with 200 ml each of ethyl acetate (insoluble matter was removed by means of Celite filtration). The ethyl acetate layer was dried over anhydrous sodium sulfate and freed of solvent by distillation to give 16.1 g of almost colorless oily residue.

The oily residue was fractionated on silica gel column chromtography [developer: a benzene/ethyl acetate 20/1 (V/V) mixture] to obtain 3.60 g of (+)-p-tert.-butyl-α-methylbenzyl alcohol as colorless crystals having a melting point of 85° C. (yield: 26.2%); [α]_(D) ²⁵ +47.8° (C=1.01, C₆ H₁₂), 98% e.e.

A part of the product (3.49 g) was recrystallized from 10.5 g of hexane to obtain 3.06 g of crystals of 100% e.e., [α]_(D) ²⁵ +48.9° (C=1.03, C₆ H₁₂).

Also, was obtained 12.1 g of (-)-p-tert.-butyl-α-methylbenzyl acetate as an almost colorless oil (yield: 71.5%) of [α]_(D) ²⁵ -36.9° (C=1.09, C₆ H₁₂), 35.6% e.e.

To 25 ml of ethyl were added 1.78 g of (+)-4-tert.-butyl-α-methylbenzyl alcohol of 100% e.e. and 1.8 g of dry pyridine. The resulting mixed solution was kept at -25° C. and added dropwise with a solution of 3.1 g of phosphorus tribromide dissolved in 18 ml of ethyl ether (at -15° to -25° C.). After completion of addition, the resulting mixture was stirred at -10° C. for one hour and then allowed to stand at 5° C. for 2 days. Ice water was added thereto. The resulting organic layer was washed successively with a saturated aqueous solution of sodium bicarbonate and with ice water, dried with anhydrous Glauber's salt, and freed of solvent by distillation under reduced pressure to give 1.6 g of 4-tert.-butyl-α-methylbenzyl bromide.

The resulting product 0.96 g was added to a mixed solution of 0.87 g of 2-tert.-butyl-4-chloro-5-mercapto-3(2H)-pyridazinone, 20 ml of hexamethyl phosphoric triamide and 0.25 g of anhydrous sodium carbonate at -20° C. The resulting mixture was allowed to stand for 2 days at room temperature. Then the mixture was incorporated with 300 ml of benzene and washed twice with water. The resulting organic layer was dried with anhydrous Glauber's salt, and freed of solvent by distillation to obtain a crude product. The crude product was purified by means of thin-layer chromatography (using a benzene/ethyl acetate.50/1 mixture, R_(f) =0.5). Hexane was added to 1.1 g of the product thus obtained to give 0.83 g of crystals.

The compound thus obtained was identical with that obtained in Synthesis Example 5 according to ¹ H-NMR measurement.

m.p.: 102.3°-104.3° C.

[α]_(D) ²⁵ +0.96° (C=1.0, CDCl₃).

SYNTHESIS EXAMPLE 7 Synthesis of (-)2-tert.-butyl-4-chloro-5-(4-tert.-butyl-α-methylbenzylthio-3(2H)-pyridazinone (Compound No. 72)

In 400 ml of 0.2M aqueous solution of disodium hydrogen-phosphate was suspended 22.6 g of (-)-p-tert.-butyl-α-methylbenzyl acetate of [α]_(D) ²⁵ -36.9° (C=1, C₆ H₁₂) and optical purity 35.6% e.e. obtained in Synthesis Example 6, and 1.33 g of chicken liver acetone powder was added thereto. The resulting mixture was subjected to reaction at 25° C. for 67 hours. The reaction liquid was extracted twice with 400 ml each of ethyl acetate (insoluble matter was removed by Celite filtration). The ethyl acetate layer was dried over anhydrous sodium sulfate and freed of solvent by distillation. The resulting pale yellow oily residue was subjected to column chromatography (on 200 g of silica gel, wherein p-tert.-butyl-α-methylbenzyl acetate was eluted with a benzene/ethyl acetate 50/1 (V/V) mixture and then p-tert.-butyl-α-methylbenzyl alcohol was eluted with benzene/ethyl acetate 10/1 (V/V) mixture and, thereafter, the solvent in each elute was distilled away). Thus were obtained 14.01 g (yield: 62%) of (-)-p-tert.-butyl-α-methylbenzyl acetate of [α]_(D) ²⁵ -85.5° (C=1.07, C₆ H₁₂), optical purity 82.6% e.e. and 6.25 g (yield 34%) of (+)-p-tert.-butyl-α-methylbenzyl alcohol of [α]_(D) ²⁵ +23.1° (C=1.07, C₆ H₁₂), optical purity 47.2% e.e.

In 33.6 ml of methanol was dissolved 13.79 g (62.6 m mol) of (-)-p-tert.-butyl-α-methylbenzyl acetate of [α]_(D) ²⁵ -85.5° (C=1.07, C₆ H₁₂), optical purity 82.6% e.e. After the resulting solution was stirred and ice-cooled, 21.7 g of 15% aqueous solution of sodium hydroxide (sodium hydroxide 81.4 m mol) was added thereto dropwise over 5 minutes.

After the resulting mixture was allowed to cool to room temperature, it was stirred for one hour and then incorporated with 100 ml of water and 100 ml of benzene for extraction. The aqueous layer was extracted again with 30 ml of benzene. The benzene layers were combined, washed with water, dried over anhydrous sodium sulfate and freed of solvent by distillation to obtain 10.86 g (yield: 97%) of colorless (-)-p-tert.-butyl-α-methylbenzyl alcohol; [α]_(D) ²⁵ -41.1° (C=1.03, C₆ H₁₂), 84.0% e.e.

A portion (10.6 g) of the product was recrystallized from 31.8 g of hexane to obtain 8.20 g of (-)-p-tert.-butyl-α-methylbenzyl alcohol of [α]_(D) ²⁵ -47.8° (C=1.00, C₆ H₁₂), optical purity 97.8% e.e.

Then, procedure similar to that in Synthesis Example 6 was conducted. Namely, reaction and purification similar to those in Synthesis Example 6 was conducted except using 1.78 g of (-)-4-tert.-butyl-α-methylbenzyl alcohol (enantiomer of the product in Synthesis Example 6) having optical rotation (-) and optical purity 97.8% e.e. instead of 1.78 g of the (+) isomer thereof to obtain 0.62 g of crystals of the intended compound. The compound was identical with that obtained in Synthesis Example 5 according to ¹ H--NMR measurement.

m.p. 102.2-106.7° C.

[α]_(D) ²⁵ -1.14° (C=1.0, CHCl₃).

SYNTHESIS EXAMPLE 8 Synthesis of 2-tert.-butyl-4-chloro-5-[4'-(4"-trifluoromethylphenoxy)benzylthio]-3(2H)-pyridazinone (Compound No. 243)

In 30 ml of N,N-dimethylformamide were dissolved 2.2 g (0.01 mol) of 2-tert.-butyl-4-chloro-5-mercapto-3(2H)-pyridazinone and 3.5 g (0.0105 mol) of 4-(4'-trifluoromethylphenoxy) benzyl bromide, and thereto was added 2.1 g (0.02 mol) of anhydrous sodium carbonate to effect reaction at 85° to 90° C. for 4 hours. After the reaction, the reaction liquid was allowed to cool, poured into water and then extracted with benzene. The benzene layer was washed with 5% aqueous solution of sodium hydroxide and then with water, dried over anhydrous sodium sulfate and then freed of benzene by distillation under reduced pressure. The oily residue was incorporated with n-hexane and the precipitated crystals were filtered off to obtain white crystals (yield: 85.5%).

m.p. 152.0°-155.5° C.

¹ H--NMR(CDCl₃), δ(ppm): 1.60(9H, s, 2-t-Bu), 4.22(2H, s, --SCH₂ --), 6.92-7.60(9H, m, phenyl and 6-H).

SYNTHESIS EXAMPLE 9 Synthesis of 2-tert.-butyl-4-bromo-5-(4-tert.-butylbenzylthio)-3(2H)-pyridazinone (Compound No. 139)

To a dimethylformamide solution of 4.4 g of 2-tert.-butyl-4-bromo-5-mercapto-3(2H)-pyridazinone and 4.7 g of 4-tert.-butylbenzyl bromide was added 3.5 g of sodium carbonate. The resulting reaction liquid was stirred at 80° C. for 4 hours, allowed to cool to room temperature, incorporated with water and extracted with benzene. The benzene layer was washed with 3% aqueous solution of sodium hydroxide and then with water, dried and then freed of benzene by distillation to give yellowish brown solid. The solid was recrystallized from a mixed solvent of benzene and n-hexane to obtain white crystals (yield: 64%).

m.p. 137.0°-139.0° C.

¹ H--NMR(CDCl₃), δ(ppm): 1.33(9H, s, 4'-t-Bu), 1.62(9H, s, 2-t-Bu), 4.21(2H, s, --SCH₂ --), 7.33(4H, m, phenyl), 7.54(1H, s, 6-H).

SYNTHESIS EXAMPLE 10 Synthesis of 2-tert.-butyl-4-chloro-5-(4-tert.-butylbenzylthio)-3(2H)-pyridazinone (Compound No. 81)

A mixture of 1.5 g of 2-tert.-butyl-4-chloro-5-mercapto-3(2H)-pyridazinone, 200 ml of benzene, 1.5 g of anhydrous potassium carbonate and 1.4 g of 4-tert.-butyl-benzyl chloride was subjected to reaction at a reflux temperature for 6 hours. Then, procedure similar to that in Synthesis Example 5 was conducted to obtain white crystals (yield: 60%).

The compound thus obtained was identical with that obtained in Synthesis Example 4 according to ¹ H--NMR measurement.

SYNTHESIS EXAMPLE 11 Synthesis of 2-tert.-butyl-4-chloro-5-(4-chlorobenzylthio)-3(2H)-pyridazinone (Compound No. 175)

Sodium hydroxide 0.7 g was dissolved in 15 ml of water, and thereto were added 100 ml of benzene, 3.3 g of 2-tert.-butyl-4,5-dichloro-3(2H)-pyridazinone and 0.15 g of triethylbenzylammonium chloride. The resulting solution was incorporated with 2.4 g of 4-chlorobenzyl mercaptan at room temperature and then stirred for 15 hours. After completion of the reaction, only the organic layer was separated therefrom, washed with a 5% aqueous solution of sodium hydroxide and then with water, and dried over anhydrous sodium sulfate. Solvent was distilled away therefrom under reduced pressure. The resulting oily residue was incorporated with hexane to give crystals. The crystals were filtered off to obtain 3.3 g of the intended compound (yield: 64%).

m.p. 142.0°-143.0° C.

¹ H--NMR(CDCl₃), δ(ppm): 1.60(9H, s, t-Bu), 4.20(2H, s, --SCH₂ --), 7.32(4H, s, phenyl), 7.56(1H, s, 6-H).

SYNTHESIS EXAMPLE 12 Synthesis of 2-tert.-butyl-4-bromo-5-(4-tert.-butylbenzylthio)-3(2H)-pyridazinone (Compound No. 139)

Sodium hydroxide 0.22 g was dissolved in 5 ml of water, and thereto were added 10 ml of dichloromethane, 1.55 g of 2-tert.-butyl-4,5-dibromo-3(2H)-pyridazinone and 0.05 g of triethylbenzylammonium chloride. The resulting solution was incorporated with 0.83 g of 4-tert.-butyl-benzyl mercaptan at room temperature and then stirred for 10 hours. After completion of the reaction, about 50 ml of CH₂ Cl₂ was added to the solution and the organic layer was separated therefrom, washed with 5% aqueous solution of sodium hydroxide and then with water, and dried over anhydrous sodium sulfate. Solvent was distilled away therefrom under reduced pressure and the resulting solid residue was recrystallized from a benzene/n-hexane mixed solvent to obtain 1.32 g of the intended compound (yield: 65%).

m.p. 137.0°-139.0° C.

¹ H--NMR(CDCl₃), δ(ppm): 1.33(9H, s, t-Bu), 1.62(9H, s, t-Bu), 4.21(2H, s, --SCH₂ --), 7.33(4H, s, phenyl), 7.54(1H, s, 6-H).

SYNTHESIS EXAMPLE 13 Synthesis of 2-tert.-butyl-4-chloro-5-(4-tert.-butylbenzylthio-3(2H)-pyridazinone (Compound No. 81)

Sodium hydroxide 0.7 g was dissolved in 15 ml of water, and thereto were added 30 ml of dichloromethane, 3.3 g of 2-tert.-butyl-4,5-dichloro-3(2H)-pyridazinone and 0.15 g of triethylbenzylammonium chloride. The resulting solution was incorporated with 2.7 g of 4-tert.-butylbenzyl mercaptan at room temperature and then stirred for 15 hours. After completion of the reaction, only the organic layer was separated therefrom, washed with a 5% aqueous solution of sodium hydroxide and then with water, and dried over anhydrous sodium sulfate. Solvent was distilled away therefrom under reduced pressure and the resulting oily residue was incorporated with hexane to give crystals. The crystals were filtered off to obtain 3.8 g of the intended compound (yield: 70%).

The physical properties of the compound were identical with those of the product of Synthesis Example 4.

The compounds produced according to one of the processes in Synthesis Examples 3 through 10 are listed in Table 3 below.

Incidentally, the compounds produced in Synthesis Examples 3 through 10 are also included in Table 3.

                                      TABLE 3                                      __________________________________________________________________________     The compounds of the formula I:                                                 ##STR153##                            (I)                                     Compound                                                                       No.   R  R.sup.1                                                                           R.sup.2                                                                          R.sup.4                                                                          R.sup.3 n       M.P. (°C.)                              __________________________________________________________________________     1     Et H  H Cl                                                                               4-t-Bu          123.0-124.5                                    2     Et H  H Cl                                                                               4-F             106.0-108.5                                    4     Et H  H Cl                                                                                ##STR154##     140.0-143.0                                    14    n-Pr                                                                              H  H Cl                                                                               4-t-Bu          159.0-161.0                                    29    i-Pr                                                                              H  H Cl                                                                               3,4-Cl.sub.2    181.0-187.0                                    30    i-Pr                                                                              H  H Cl                                                                               4-t-Bu          141.0-142.0                                    70    t-Bu                                                                              Me H Cl                                                                               4-t-Bu          100.0-106.0                                    71    optically active compound (+) of Compound No. 70                                                         102.3-104.3                                    72    optically active compound (-) of Compound No. 70                                                         102.2-106.7                                    73    t-Bu                                                                              H  H Cl                                                                                ##STR155##     170.0-176.0                                    74    t-Bu                                                                              H  H Cl                                                                                ##STR156##     169.1-171.5                                    75    t-Bu                                                                              H  H Cl                                                                                ##STR157##     112.1-113.5                                    76    t-Bu                                                                              H  H Cl                                                                                ##STR158##     198.2-199.6                                    77    t-Bu                                                                              H  H Cl                                                                               2-Me            138.0-139.0                                    78    t-Bu                                                                              H  H Cl                                                                               3-Me            86.5-87.5                                      79    t-Bu                                                                              H  H Cl                                                                               4-Me            119.0-120.0                                    80    t-Bu                                                                              H  H Cl                                                                               4-i-Pr          96.5-98.0                                      81    t-Bu                                                                              H  H Cl                                                                               4-t-Bu          111.0-112.0                                    84    t-Bu                                                                              H  H Cl                                                                               3,4-Cl.sub.2    111.0-112.0                                    87    t-Bu                                                                              H  H Cl                                                                               4-F             112.5-114.0                                    88    t-Bu                                                                              H  H Cl                                                                                ##STR159##     157.0-159.0                                    95    t-Bu                                                                              H  H Cl                                                                                ##STR160##     169.0-171.0                                    97    t-Bu                                                                              H  H Cl                                                                               4-Br            144.0-146.0                                    101   t-Bu                                                                              Me H Cl                                                                               3-Me            118.0-119.0                                    102   t-Bu                                                                              Me H Cl                                                                               4-Me            83.0-84.0                                      103   t-Bu                                                                              Me H Cl                                                                               4-i-Pr          73.0-74.5                                      104   t-Bu                                                                              H  H Cl                                                                                ##STR161##     129.0-131.0                                    106   t-Bu                                                                              Me H Cl                                                                                ##STR162##     102.0-104.0                                    107   t-Bu                                                                              Me H Cl                                                                               4-Br            122.5-123.5                                    108   t-Bu                                                                              Me H Cl                                                                               4-Cl            98.5-99.5                                      109   t-Bu                                                                              Me H Cl                                                                                ##STR163##     140.0-142.0                                    110   t-Bu                                                                              Et H Cl                                                                               4-t-Bu          oil                                            112   t-Bu                                                                              H  H Cl                                                                               2-NO.sub.2      121.0                                          115   t-Bu                                                                              Et H Cl                                                                               4-Cl            oil                                            126   t-Bu                                                                              H  H Cl                                                                                ##STR164##     143.0-146.0                                    127   t-Bu                                                                              H  H Cl                                                                                ##STR165##     120.0-122.2                                    128   t-Bu                                                                              H  H Cl                                                                                ##STR166##     110.0-111.0                                    129   t-Bu                                                                              H  H Cl                                                                               4-OCH.sub.2 CHCH.sub.2                                                                         59.0-68.0                                      130   t-Bu                                                                              H  H Cl                                                                               4-SC.sub.4 H.sub.9n                                                                            oil                                            131   t-Bu                                                                              H  H Cl                                                                               4-SMe           semi solid                                     132   t-Bu                                                                              H  H Cl                                                                               3-OC.sub.4 H.sub.9n                                                                            semi solid                                     133   t-Bu                                                                              H  H Cl                                                                               4-Si(Me).sub.3  99.6-101.4                                     134   t-Bu                                                                              Me H Cl                                                                                ##STR167##     149.0-150.0                                    135   t-Bu                                                                              Me H Cl                                                                                ##STR168##     118.0-120.0                                    136   t-Bu                                                                              H  H Cl                                                                               4-SCHF.sub.2    77.0-77.5                                      137   t-Bu                                                                              H  H Cl                                                                               4-OCH.sub.2 CH.sub.2 CH.sub.2 Cl                                                               semi solid                                     138   t-Bu                                                                              H  H Cl                                                                               4-OCHF.sub.2    75.0-78.0                                      139   t-Bu                                                                              H  H Br                                                                               4-t-Bu          137.0-139.0                                    140   t-Bu                                                                              H  H Br                                                                               4-Cl            163.0-165.0                                    141   t-Bu                                                                              H  H Cl                                                                                ##STR169##     68.0-68.3                                      142   t-Bu                                                                              H  H Cl                                                                               4-C(Me).sub.2 CH.sub.2 Cl                                                                      127.0-129.0                                    143   t-Bu                                                                              H  H Cl                                                                               4-OCHC(Me)CH.sub.2                                                                             98.6- 100.0                                    144   t-Bu                                                                              H  H Cl                                                                               3,5-(t-Bu).sub.2, 4-OH                                                                         164.7-166.3                                    145   t-Bu                                                                              H  H Cl                                                                               3,5-(Br).sub.2, 4-OH                                                                           191.7-193.4                                    146   t-Bu                                                                              H  H Br                                                                                ##STR170##     147.0-152.0                                    147   t-Bu                                                                              H  H Br                                                                               4-n-C.sub.4 H.sub.9                                                                            84.0-86.0                                      148   t-Bu                                                                              H  H Br                                                                               4-OC.sub.6 H.sub.13n                                                                           71.0-73.0                                      149   t-Bu                                                                              Me H Br                                                                                ##STR171##     Oil                                            150   t-Bu                                                                              H  H Cl                                                                               4-N(Me).sub.2   136.5-140.0                                    151   t-Bu                                                                              H  H Cl                                                                               3-OMe, 4-OPri   86.0-88.0                                      152   t-Bu                                                                              H  H Cl                                                                               4-I             117.0-118.0                                    153   t-Bu                                                                              H  H Cl                                                                               4-OEt           90.0-91.0                                      154   t-Bu                                                                              H  H Cl                                                                               4-OC.sub.3 H.sub.7n                                                                            105.0-106.0                                    155   t-Bu                                                                              H  H Cl                                                                               4-i-Bu          125.0-129.0                                    156   t-Bu                                                                              H  H Cl                                                                               4-n-Bu          92.0-94.0                                      157   t-Bu                                                                              H  H Cl                                                                               4-n-C.sub.6 H.sub.13                                                                           104.0-106.0                                    158   t-Bu                                                                              H  H Cl                                                                               4-n-C.sub.7 H.sub.15                                                                           semi solid                                                                     (4-position 80%,                                                               2-position 20%)                                159   t-Bu                                                                              H  H Cl                                                                               4-n-C.sub.8 H.sub.17                                                                           55.0-65.0                                                                      (4-position 70%,                                                               2-position 30%)                                160   t-Bu                                                                              H  H Cl                                                                               4-sec.-Bu       95.0-97.0                                      161   t-Bu                                                                              H  H Cl                                                                               4-t-C.sub.5 H.sub.11                                                                           142.0-143.0                                    162   t-Bu                                                                              H  H Cl                                                                               4-COOMe         117.0-122.0                                    163   t-Bu                                                                              H  H Cl                                                                               4-OPri          131.0-132.5                                    164   t-Bu                                                                              H  H Cl                                                                               4-OCH.sub.2 CH(Et)Bun                                                                          oil                                            165   t-Bu                                                                              H  H Cl                                                                               4-OC.sub.9 H.sub.19n                                                                           oil                                            166   t-Bu                                                                              H  H Cl                                                                               4-OC.sub.11 H.sub.23n                                                                          oil                                            167   t-Bu                                                                              Me H Cl                                                                               4-OC.sub.10 H.sub.21n                                                                          oil                                            168   t-Bu                                                                              H  H Cl                                                                               4-OC.sub.4 H.sub.9n                                                                            89.0-89.5                                      169   t-Bu                                                                              H  H Cl                                                                               4-OC.sub.5 H.sub.11n                                                                           88.0-88.5                                      170   t-Bu                                                                              H  H Cl                                                                               4-OC.sub.6 H.sub.13n                                                                           85.0-86.0                                      171   t-Bu                                                                              H  H Cl                                                                               4-OC.sub.7 H.sub.15n                                                                           77.0-78.0                                      172   t-Bu                                                                              H  H Cl                                                                               4-OC.sub.8 H.sub.17n                                                                           64.0-66.0                                      173   t-Bu                                                                              H  H Cl                                                                               2,6-(Me).sub.2, 4-t-Bu                                                                         207.0-208.5                                    174   t-Bu                                                                              H  H Cl                                                                               3,5-Br.sub.2, 4-OPri                                                                           46.0-48.0                                      175   t-Bu                                                                              H  H Cl                                                                               4-Cl            142.0-143.0                                    176   t-Bu                                                                              H  H Cl                                                                               4-CF.sub.3      125.0-127.0                                    177   t-Bu                                                                              H  H Cl                                                                                ##STR172##     132.0-133.0                                    178   t-Bu                                                                              H  H Cl                                                                                ##STR173##     oil                                            179   t-Bu                                                                              H  H Cl                                                                               4-OCH(Me)COOEt  111.0-113.0                                    180   t-Bu                                                                              H  H Cl                                                                               4-OCH.sub.2 CHCHMe                                                                             64.0-66.0                                      181   t-Bu                                                                              H  H Cl                                                                               4-SCN           104.5-109.0                                    216   Et H  H Cl                                                                                ##STR174##     127.0-131.0                                    224   i-Pr                                                                              H  H Cl                                                                                ##STR175##     133.0-135.0                                    227   n-Pr                                                                              H  H Cl                                                                                ##STR176##     137.0-140.0                                    243   t-Bu                                                                              H  H Cl                                                                                ##STR177##     152.0-155.5                                    244   t-Bu                                                                              H  H Cl                                                                                ##STR178##     109.0-110.0                                    245   t-Bu                                                                              Me H Cl                                                                                ##STR179##     oil                                            246   t-Bu                                                                              H  H Cl                                                                                ##STR180##     146.0-147.0                                    249   t-Bu                                                                              H  H Cl                                                                                ##STR181##     oil                                            260   t-Bu                                                                              H  H Cl                                                                                ##STR182##     oil(n.sub.D.sup.20 1.6073)                     __________________________________________________________________________      [In Table 3, "Me" denotes methyl, "Et" denotes ethyl, "Pr" denotes propyl      "Bu" denotes butyl, "n" denotes normal, "t" denotes tertiary, "i" denotes      iso and "s" denotes secondary.]-                                         

When the compounds according to the present invention are used for insecticidal, acaricidal, nematicidal and/or fungicidal agents for agricultural and horticultural uses or for expellents of ticks parasitic on animals, they are generally mixed with appropriate carriers, for instance, solid carriers such as clay, talc, bentonite or diatomaceous earth, or liquid carriers such as water, alcohols (e.g. methanol and ethanol), aromatic hydrocarbons (e.g. benzene, toluene and xylene), chlorinated hydrocarbons, ethers, ketones, acid amides (e.g. dimethylformamide) or esters (e.g. ethyl acetate). If desired, to these mixtures may be added emulsifier, dipersing agent, suspension agent, penetrating agent, spreader, stabilizer and the like to put them into practical uses in the form of liquid preparation, emulsifiable concentrate, wettable powder, dust, granule, flowable or the like. Moreover, the mixtures may be incorporated with other herbicides, various insecticides, fungicides, plant-growth regulating agents and/or synergists during preparation or application thereof, as necessary.

The amounts of the compounds of the invention to be used as an active ingredient is suitably in the range of 0.005 to 5 kg per hectare although it varies depending upon the place and the season where the compounds are applied, manner of application, diseases and insect pests to be applied, cultivated crops to be protected and the like.

In the following, there are shown formulation examples of fungicidal, insecticidal, acaricidal and/or nematicidal compositions and excellent compositions for ticks parasitic on animals, said compositions containing the compounds of the present invention as an active ingredient. These examples are only illustrative and not to restrict the invention. In the following examples, "part" means "part by weight".

    ______________________________________                                         Formulation Example 1: Emulsifiable concentrates                               ______________________________________                                         Active ingredient         25 parts                                             Xylene                    55 parts                                             N,N--dimethylformamide    20 parts                                             Solpol 2680 (trade name, a mixture of                                                                     5 parts                                             a non-ionic surface-active agent and                                           an anionic surface-active agent                                                manufactured by Toho Chemicals, Co.,                                           Ltd., Japan)                                                                   ______________________________________                                    

The above components are mixed intimately together to form an emulsifiable concentrate. Upon use, the emulsifiable concentrate is diluted with water up to one five hundredth to one twenty thousandth in concentration and applied at a rate of 0.005 to 5 kg of the active ingredient per hectare.

    ______________________________________                                         Formulation Example 2: Wettable powders                                        ______________________________________                                         Active ingredient        25 parts                                              Siegreit PFP (trade name, caoline-                                                                      69 parts                                              based clay manufactured by Siegreit                                            Mining Industries Co., Ltd.)                                                   Solpol 5039 (trade name, a mixture of                                                                    3 parts                                              a non-ionic surface-active agent and                                           an anionic surface-active agent                                                manufactured by Toho Chemical Co.,                                             Ltd., Japan)                                                                   Carplex (trade name, coagulation-                                                                        3 parts                                              inhibition agent, a mixture of a                                               surface-active agent and white carbon                                          manufactured by Shionogi Seiyaku                                               K.K., Japan)                                                                   ______________________________________                                    

The above components are homogeneously mixed together and ground to form a wettable powder. Upon use, the wettable powder is diluted with water up to one five hundredth to one twenty thousandth and applied at a rate of 0.005 to 5 kg of the active ingredient per hectare.

    ______________________________________                                         Formulation Example 3: Oil solutions                                           ______________________________________                                         Active ingredient     10 parts                                                 methylcellosolve      90 parts                                                 ______________________________________                                    

The above components are homogeneously mixed together to form an oil solution. Upon use, the oil solution is applied at a rate of 0.005 to 5 kg of the active ingredient per hectare.

    ______________________________________                                         Formulation Example 4: Dusts                                                   ______________________________________                                         Active ingredient         3.0 parts                                            Carplex (trade name, coagulation-                                                                        0.5 parts                                            inhibition agent as mentioned                                                  in the above)                                                                  Clay                     95.0 parts                                            di-isopropyl phosphate    1.5 parts                                            ______________________________________                                    

The above components are homogeneously mixed together and ground to form a dust. Upon use, the dust is applied at a rate of 0.005 to 5 kg of the active ingredient per hectare.

    ______________________________________                                         Formulation Example 5: Granules                                                ______________________________________                                         Active ingredient      5 parts                                                 Bentonite              54 parts                                                Talc                   40 parts                                                Calcium lignin sulfonate                                                                               1 part                                                 ______________________________________                                    

The above components are mixed intimately together and ground, incorporated with a small amount of water and mixed together with stirring. The resulting mixture is granulated by means of extrusion-granulator and dried to form granules. Upon use, the granule is applied at a rate of 0.005 to 5 kg of the active ingredient per hectare.

    ______________________________________                                         Formulation Example 6: Flowables                                               ______________________________________                                         Active ingredient        25 parts                                              Solpol 3353 (trade name, a non ionic                                                                    10 parts                                              surface-active agent manufactured                                              by Toho Chemicals, Co., Ltd., Japan)                                           Runox 1000C (trade name, an anionic                                                                     0.5 parts                                             surface-active agent manufactured                                              by Toho Chemicals, Co., Ltd., Japan)                                           1% aqueous solution of Xanthan gum                                                                      20 parts                                              (natural high-molecular compound)                                              Water                    44.5 parts                                            ______________________________________                                    

The above components except the active ingredient are uniformly mixed together to form a solution, and thereto is added the active ingredient. The resulting mixture is throughly stirred, wet-ground by means of sand mill to form a flowable. Upon use, the flowable is diluted up to one fiftieth to one twenty thousandth with water and applied at a rate of 0.005 to 10 kg of the active ingredient per hectare.

The compounds according to the present invention not only exhibit superior insecticidal action on hemiptera insect such as green rice leafhopper (Nephotettix cincticeps), lepidoptera insect such as diamounback moth (Plutella xylostella), and sanitary insect pests such as pale house mosquito (Culex pipiens), but are also useful for expelling mites parasitic on fruits and vegetables such as two-spotted spider mite (Tetranychus urticae), Kanzawa spider mite (Tetranychus kanzawai), Carmine mite (Tetranychus cinnabarinus), citrus red mite (Panonychus citri) and European red mite (Panonychus ulmi), as well as ticks parasitic on animals such as southern cattle tick (Boophilus microplus), cattle tick (Boophilus annulatus), galf coast tick (Amblyomma maculatum), brown-ear tick (Rhipicephalus appendiculatus) and (Haemaphysalis longicornis). The main features of the compounds of the present invention resides in that the compounds are useful for the prevention or control of blight (or disease) of fruits and vegetables such as powdery mildew, downy mildew, etc. in addition to having the above mentioned insecticidal, acaricidal, nematicidal and fungicidal actions. Accordingly, the compounds of the present invention are an excellent agricultural drug which enables control of pests and blight (or disease) simultaneously. Moreover, they are excellent as an expellent for ticks parasitic on animals such as domestic animals (e.g. cattle, horse, sheep and pig), domestic fowls, and other animals such as dog, cat, rabbit and the like.

The invention is further explained in detail by way of the following test examples.

TEST EXAMPLE 1 Insecticidal test on house fly (Musca domestica) adult

One ml of acetone solution containing 1000 ppm of the compound of the invention to be tested was added dropwise to a laboratory dish of 9 cm in diameter so that the solution may be evenly spread over the dish. After completely evaporating the acetone at room temperature, 10 house fly adults were placed in the dish and then the dish was covered with a plastic cap provided with some pores. The dish containing the adults was placed in a thermostatic chamber kept at 25° C. An evaluation was made after 48 hours by counting the adults insects killed and calculating the mortality of the insect in accordance with the following equation: ##EQU1##

Incidentally, the test was repeated twice for each compound.

The results thereof are listed in Table 4.

TEST EXAMPLE 2 Insecticidal test on Pale House Mosquito (Culex pipiens) larvae

200 ml of 10 ppm aqueous solution of each compound of the invention was placed in a tall dish of 9 cm in diameter and 6 cm in height. Then, 10 of the last instar larvae of Pale House Mosquitos were released in the dish. The tall dish was placed in a thermostatic chamber kept at 25° C., and the number of the mosquitos killed was counted after 96 hours. The mortality was determined as in Test Example 1.

The above test was repeated twice for each compound.

The results are shown in Table 4.

TEST EXAMPLE 3 Contact insecticidal test on Diamondback Moth (Plutella xylostella)

A leaf of cabbage was immersed in an aqueous emulsion containing 1000 ppm of each compound of the invention for about 10 seconds, and then air-dried. The leaf thus treated was placed in a dish, into which 10 second instar diamondback moth larvae were released. The dish was fitted with a cap provided with some pores and then placed in a thermostatic chamber kept at 25° C. The mortality of the diamondback moth after 96 hours was determined in the same manner as in Test Example 1. Incidentally, the test was repeated twice for each compound.

The results thereof are shown in Table 4.

TEST EXAMPLE 4 Contact insecticidal test on 28-spotted Lady Beetle (Henosepilachna vigintioctopunctata)

A leaf of tomato was immersed in an aqueous emulsion containing 1000 ppm of each compound of the invention and then air-dried. The leaf thus treated was placed in a laboratory dish, into which 10 second inster 28-spotted lady beetle larvae were released. The dish was then fitted with a cap provided with pores and then placed in a thermostatic chamber kept at 25° C. The number of the larvae killed was checked after 96 hours and the mortality thereof was determined in the same manner as in Test Example 1. Incidentally, the test was repeated twice for each compound.

The test results are shown in Table 4.

TEST EXAMPLE 5 Acaricidal test on Kanzawa Spider Mite (T. Kanzawa)

A leaf of kidney bean was cut into a round piece of 1.5 cm in diameter by a leaf punch, and then placed on the moistened filter paper put on a styrol cup of 7 cm in diameter. Each piece of the leaf was inoculated with 10 Kanzawa Spider Mite nymphs. Half a day after the inoculation, each 2 ml of an aqueous emulsion containing 1000 ppm of a compound of the invention diluted with a spreader was applied to each styrol cup by means of a rotary spray tower. The number of the nymph killed was checked after 96 hours and the mortality of the nymph was determined as in Test Example 1. Incidentally, the test was repeated twice for each compound.

The results are shown in Table 4.

TEST EXAMPLE 6 Acaricidal test on Citrus red mite (Panonychus citri)

A leaf of Mandarin orange was cut into a round piece of 1.5 cm in diameter by a leaf punch, and then placed on the moistened filter paper put on a styrol cup of 7 cm in diameter. Each piece of the leaf was inoculated with 10 Citrus red mite nymphs. Half a day after the inoculation, each 2 ml of an aqueous emulsion containing 1000 ppm of the active substance with a spreader was applied to each styrol cup by means of a rotary spray tower. The number of the nymph killed was checked after 96 hours and the mortality of the nymph was determined as in Test Example 1.

The results are shown in Table 4.

TEST EXAMPLE 7 Insecticidal test on Green rice leafhopper (Nephotettix cincticeps)

Stems and leaves of paddy were immersed into 1000 ppm emulsion of each compound of the invention for 10 seconds, and then the stems and leaves were placed into a glass cylinder. After 10 adults of green rice leafhopper which would show resistance to organic phosphorus type insecticides were released, the glass sylinder was covered with a lid having some pores and placed in a thermostatic chamber kept at 25° C. After 96 hours later, the mortality was determined as in Test Example 1. Incidentally, the test was repeated twice for each compound.

The results are shown in Table 4.

TEST EXAMPLE 8 Nematicidal test on Root-knot Nematode (Meloidogyne spp.)

Soil contaminated with root-knot nematode was placed in a styrol cup of 8 cm in diameter. A liquid containing 1000 ppm of an active ingredient was prepared by diluting an emulsifiable concentrate according to the present invention with water and then a spreader was added thereto. The soil contaminated with nematode and placed in the styrol cup was drenched with each 50 ml of the resulting liquid. After 48 hours, a tomato seedling as an indicator was transplanted into the soil thus treated. 30 days after the transplantation, the roots of the tomato were washed with water and the root-knot parasitism was checked by observation and evaluated according to the following rating:

Rating of root-knot parasitism

0: no root-knot observed at all.

1: a few root-knots observed.

2: a medium number of root-knot observed.

3: many root-knots observed.

4: considerably many root-knots observed.

Incidentally, the test was repeated twice for each compound. The results are shown in Table 4.

TEST EXAMPLE 9 Test for controlling Downy mildew of cucumber

Employing cucumbers (Cucumis sativus L.: variety Sagamihanjiro) which had been grown for about 2 weeks, thereto was sprayed a solution of an emulsifiable concentrate according to the invention which had been adjusted to a predetermined concentration (1000 ppm) at the rate of 20 ml per pot. After each pot was placed overnight in a greenhouse, a suspension of spores of Pseudoperonospora cubensis (the concentration of the spores being such that when observed by a 150 magnification microscope, 15 pieces of the spore may be present) was sprayed to the cucumbers for inoculation. The cucumbers to which the spores of Pseudoperonospora cubensis had been inoculated were left for 24 hours in a room kept at 25° C. with a relative humidity of 100% and then transported to a greenhouse for observation of disease appearance. Seven days after the inoculation, the percentages of the disease appearance were measured and evaluated according to the following rating:

0: no disease appearance

1: disease appearance being not more than 5% of the inoculated leaves

2: disease appearance being 6-20% of the inoculated leaves

3: disease appearance 21-50% of the inoculated leaves

4: disease appearance 51-90% of the inoculated leaves

5: disease appearance being not less than 90% of the inoculated leaves.

The results are shown in Table 5-I.

TEST EXAMPLE 10 Test for controlling Powdery mildew of cucumber

Employing cucumbers (Cucumis sativus L.: variety Sagamihanjiro) which had been grown in pots for about 2 weeks, thereto was sprayed a solution of an emulsifiable concentrate according to the present invention which had been adjusted to a predetermined concentration (1000 ppm) at the rate of 20 ml per pot. After each pot was placed overnight in a greenhouse, a suspension of spores of Sphaerotheca fuliginea (the concentration of the spores being such that when observed by a 150 magnification microscope, 25 pieces of the spores may be present) was sprayed to the cucumbers for inoculation. The cucumbers were placed in a greenhouse at 25°-30° C. for observation of disease appearance. Ten days after the inoculation, the percentages of the disease appearance were measured and evaluated according to the same rating as in Test Example 9.

The results are shown in Table 5-II.

Next, the expelling action of the compounds of the invention on ticks parasitic on animals is explained in detail by way of the following test examples.

TEST EXAMPLE 11 Acaricidal test on Haemaphysalis longicornis

A 1000 ppm acetone solution of a compound of the invention and an acetone solution as a control were prepared. Inside of a cylindrical glass vessel (2.8 cm in diameter and 10.5 cm in height) was set, to provide a test vessel, a cylindrical filter having an inner surface of 142.9 cm², side surface of 130.6 cm² and total surface of bottom and cap surfaces of 24.6 cm², wherein the filter had previously been immersed in one of the above-mentioned solutions and then dried sufficiently. After 20 tick nymphs were released in this test vessel, the vessel was fitted with a cap provided with the filter and applied with a cotton stopper. After a predetermined time elapsed, the filter was taken out from the vessel, irradiated with light by means of the condenser of a microscope under a binocular stereomicroscope, and observed on migration of the body and movement of the legs of the ticks. Evaluation of life and death of tick was made by regarding such tick as alive that moves its body and legs.

Incidentally, the tick tested is an un-bloodsuck tick nymph which has been incubated from the egg laid by parthenogenetic female tick adult (Haemaphysalis longicornis) of Okayama strain which had previously been allowed to such blood from a domestic rabbit.

The results are shown in Table 6.

                                      TABLE 4                                      __________________________________________________________________________                              28-spotted                                                        Pale-house                                                                           Diamondback                                                                           lady beetle     Citrus Green rice                           House fly                                                                            mosquito                                                                             moth   (Henosepilachna                                                                         Kanzawa                                                                               red mite                                                                              leafhopper                                                                            Root-knot                     (Musca                                                                               (Culex                                                                               (Plutella                                                                             vigintiociol-                                                                           spider mite                                                                           (Panonychus                                                                           (Nephotettix                                                                          nematode                Compound                                                                             domestica)                                                                           pipiens)                                                                             xylostella                                                                            punctata)                                                                               (T. kanzawai                                                                          citri) cincticeps)                                                                           (Meloidogyme            No.   (1000 ppm)                                                                           (10 ppm)                                                                             (1000 ppm)                                                                            (1000 ppm)                                                                              (1000 ppm)                                                                            (1000 ppm)                                                                            (1000 ppm)                                                                            sp.) (1000              __________________________________________________________________________                                                            ppm)                    1     100   100   100    100      100    100    100    0                       4     100   100   100    100      90     100    100    1                       14    --    65    95     100      95     100    100    1                       70    100   100   100    100      100    100    100    0                       72    100   100   100    100      100    100    100    0                       73    --    --    --     100      100    100    --     0                       75    100   100   --     100      100    100    100    0                       78    70    90    80     100      100    100    100    0                       79    75    95    85     100      100    100    100    0                       80    100   100   100    100      100    100    100    0                       81    100   100   100    100      100    100    100    0                       84    100   100   100    75       100    100    100    1                       87    100   100   100    100      100    100    100    1                       88    100   100   100    100      100    100    100    0                       95    100   100   100    100      100    100    100    0                       97    80    90    100    100      95     100    100    0                       101   100   100   100    100      70     100    100    0                       102   100   100   100    100      100    100    100    0                       103   100   100   100    100      100    100    100    0                       104   100   100   100    100      100    100    100    0                       106   100   100   100    100      100    100    100    0                       107   100   100   100    100      85     100    100    0                       108   100   100   100    100      100    100    100    0                       109   100   100   100    100      100    100    100    0                       110   --    --    70     90       100    100    100    0                       115   100   100   85     70       90     100    100    1                       126   --    100   --     100      100    100    100    1                       127   --    100   --     100      100    100    100    1                       128   --    100   --     100      100    100    100    0                       129   100   100   100    100      100    100    100    0                       130   100   100   100    100      100    100    100    0                       131   100   100   --     100      100    100    100    0                       132   100   100   100    100      100    100    100    0                       133   100   100   --     100      100    100    100    0                       134   100   100   100    100      100    100    100    0                       135   100   100   100    100      100    100    100    0                       136   100   100   --     100      100    100    100    0                       137   100   100   100    100      100    100    100    0                       138   100   100   100    100      100    100    100    0                       139   --    --    --     100      100    100    100    0                       141   100   100   --     100      100    100    100    0                       142   100   100   --     100      100    100    100    0                       143   --    100   --     100      100    100    100    0                       146   100   100   --     100      100    100    100    0                       147   --    100   --     100      100    100    100    0                       148   100   100   --     100      100    100    100    0                       149   100   100   100    100      100    100    100    0                       150   100   100   --     --       100    100    100    1                       151   100   100   100    100      100    100    100    0                       152   --    100   --     100      --     100    100    0                       153   100   100   100    100      100    100    100    0                       154   100   100   100    100      100    100    100    0                       155   100   100   100    100      100    100    100    0                       156   100   100   100    100      100    100    100    0                       157   100   100   100    100      100    100    100    0                       158   100   100   --     100      100    100    100    0                       159   100   --    --     100      100    100    100    0                       160   100   100   --     100      100    100    100    0                       161   100   --    --     100      100    100    100    0                       162   100   100   --     --       --     --     100    0                       163   100   100   100    100      100    100    100    0                       164   100   100   --     100      100    100    --     0                       165   100   100   --     100      100    100    100    0                       166   --    --    100    100      100    100    100    0                       167   --    --    100    100      100    100    100    0                       168   100   100   100    100      100    100    100    0                       169   100   100   100    100      100    100    100    0                       170   100   100   100    100      100    100    100    0                       171   100   100   --     100      100    100    100    0                       172   100   100   --     100      100    100    100    0                       174   --    --    --     100      100    100    100    0                       176   --    100   100    100      100    100    100    0                       177   --    100   100    100      100    100    100    0                       178   100   100   --     100      --     100    100    --                      180   100   100   100    100      100    100    100    0                       216   100   100   100    100      70     100    100    1                       224   100   100   95     100      100    100    100    1                       227   100   100   95     100      100    100    100    0                       243   100   100   100    100      100    100    100    0                       244   100   100   100    100      100    100    100    0                       245   100   100   100    100      100    100    --     0                       246   --    --    --     --       100    100    100    0                       249   100   100   95     100      100    100    100    1                       __________________________________________________________________________

                  TABLE 5-I                                                        ______________________________________                                         (Test for controlling Downy mildew of cucumber)                                Compound    Degree of disease                                                  No.         appearance (1000 ppm)                                              ______________________________________                                          1          0                                                                   4          0                                                                   30         0                                                                   81         0                                                                   95         0                                                                   97         0                                                                  102         0                                                                   70         0                                                                  109         0                                                                  127         0                                                                  131         0                                                                  134         0                                                                  136         0                                                                  138         0                                                                  152         0                                                                  153         0                                                                  176         0                                                                  181         0                                                                  227         0                                                                  243         0                                                                  ______________________________________                                    

                  TABLE 5-II                                                       ______________________________________                                         (Test for controlling Powdery mildew of cucumber)                              Compound    Degree of disease                                                  No.         appearance (1000 ppm)                                              ______________________________________                                          1          0                                                                   78         0                                                                   80         0                                                                   81         0                                                                   87         0                                                                   95         0                                                                   70         0                                                                  112         0                                                                  133         0                                                                  138         0                                                                  139         0                                                                  141         0                                                                  149         0                                                                  176         0                                                                  ______________________________________                                    

                  TABLE 6                                                          ______________________________________                                         Acaricidal test on Haemaphysalis longicornis                                          Concentration                                                                            Ticks killed after treatment (%)                              Compound of solution 24 hours    48 hours                                      No.      (ppm)       after treatment                                                                            after treatment                               ______________________________________                                          70      1,000       100         100                                            81      1,000       100         100                                           106      1,000       100         100                                           109      1,000       100         100                                           Control  --          0           0                                             (acetone                                                                       only)                                                                          ______________________________________                                     

What is claimed is:
 1. A 3(2H)-pyridazinone derivative having formula (I): ##STR183## wherein, R denotes C₂ to C₆ alkyl, R¹ and R² denote each independently hydrogen or a lower alkyl, R⁴ denotes a halogen, R³ denotes a halogen, a straight or branched C₁ to C₁₂ alkyl, a cycloalkyl unsubstituted or substituted by a lower alkyl; a straight or branched C₁ to C₁₂ alkoxy; a lower haloalkyl; a lower haloalkoxy; ##STR184## (wherein X denotes a halogen, a lower alkyl, a cycloalkyl, a lower alkoxy, a lower haloalkyl, a lower haloalkoxy, --CN or --NO₂, and m denotes 0 or an integer of 1 to 5, said X being the same or different when m is an integer of 2 to 5); a pyridyloxy which may be substituted by a halogen and/or --CF₃ ; a quinoxalyloxy which may be substituted by a halogen and/or --CF₃ ; a lower alkenyloxy; a lower alkylthio; a lower haloalkylthio; --Si(CH₃)₃ ; --OH; --N(CH₃)₂ ; --SCN; --COOCH₃ ; or --OCH(CH₃)COOC₂ H₅, and n denotes an integer of 1 to 5, said R³ being the same or different when n is an integer of 2 to
 5. 2. A 3(2H)-pyridazinone derivative having formula (I): ##STR185## wherein, R denotes C₂ to C₆ alkyl, R¹ and R² denote each independently hydrogen or a lower alkyl, R⁴ denotes a halogen, R³ denotes a halogen, a straight or branched lower alkyl, a cycloalkyl unsubstituted or substituted by a lower alkyl; a straight or branched lower alkoxy; a lower haloalkyl; a lower haloalkoxy; ##STR186## (wherein X denotes a halogen, a lower alkyl, a cycloalkyl, a lower haloalkyl, a lower haloalkyl, a lower haloalkoxy, --CN or --NO₂, and m denotes 0 or an integer of 1 to 2, said X being the same or different when m is an integer of 2); and n denotes an integer of 1 to 5, said R³ being the same or different when n is an integer of 2 to
 5. 3. Insecticidal, acaricidal, nematicidal and/or fungicidal compositions for agricultural and horticultural uses and expellent compositions for ticks parasitic on animals, said compositions containing as an active ingredient at least one of the 3(2H)-pyridazinone derivatives having the general formula I: ##STR187## wherein, R denotes a straight or branched C₂ to C₆ alkyl, R¹ and R² denote each independently hydrogen or a lower alkyl, R⁴ denotes a halogen, R³ denotes a halogen; a straight or branched C₁ to C₁₂ alkyl; a cycloalkyl unsubstituted or substituted by a lower alkyl; a straight or branched C₁ to C₁₂ alkoxy; a lower haloalkyl; a lower haloalkoxy; ##STR188## (wherein X denotes a halogen, a lower alkyl, a cycloalkyl, a lower alkoxy, a lower haloalkyl, a lower haloalkoxy, --CN or --NO₂ and m denotes 0 or an integer of 1 to 5, said X being the same or different when m is an integer of 2 to 5); a pyridyloxy which may be substituted by a halogen and/or --CF₃ ; a quinoxalyloxy which may be substituted by a halogen and/or --CF₃ ; a lower alkenyloxy; a lower alkylthio; a lower haloalkylthio; --Si(CH₃)₃ ; --OH; --N(CH₃)₂ ; --SCN; --COOCH₃ ; or --OCH(CH₃)COOC₂ H₅, and n denotes an integer of 1 to 5, said R³ being the same or different when n is an integer of 2 to 5; and a suitable carrier.
 4. A method for insecticidal, acaricidal, and/or fungicidal treatment in the agricultural and horticultural field by applying an effective amount of a compound of the formula (I) of claim
 1. 5. 2-tert.-butyl-4-chloro-5-(4-tert.-butyl-.alpha.-methylbenzylthio)-3(2H)-pyridazinone of claim 1 of the formula: ##STR189##
 6. 2-tert.-butyl-4-chloro-5-(4-tert.-butylbenzylthio-3(2H)-pyridazinone of claim 1 of the formula: ##STR190##
 7. 2-tert.-butyl-4-chloro-5-(4-cyclohexylbenzylthio)-3(2H)-pyridazinone of claim 1 of the formula: ##STR191##
 8. 2-tert.-butyl-4-chloro-5-(4-phenyl-benzylthio)-3(2H)-pyridazinone of claim 1 of the formula: ##STR192##
 9. 2-tert.-butyl-4-chloro-5-(4-cyclohexyl-α-methylbenzylthio)-3(2H)-pyridazinone of claim 1 of the formula: ##STR193##
 10. 2-tert.-butyl-4-chloro-5-(4-phenyl-α-methylbenzylthio)-3(2H)-pyridazinone of claim 1 of the formula: ##STR194##
 12. A 3(2H)-pyridazinone derivative of the formula (I): ##STR196## wherein, R denotes tert.-butyl, R¹ and R² denote each independently hydrogen or a lower alkyl, R⁴ denotes a halogen, R³ denotes a halogen, a straight or branched C₁ to C₁₂ alkyl, a cycloalkyl unsubstituted or substituted by a lower alkyl; a straight or branched C₁ to C₁₂ alkoxy; a lower haloalkyl; a lower haloalkoxy; ##STR197## (wherein X denotes a halogen, a lower alkyl, a cycloalkyl, a lower alkoxy, a lower haloalkyl, a lower haloalkoxy, --CN or --NO₂, and m denotes 0 or an integer of 1 to 5, said X being the same or different when m is an integer of 2 to 5); a pyridyloxy which may be substituted by a halogen and/or --CF₃ ; a quinoxalyloxy which may be substituted by a halogen and/or --CF₃ ; a lower alkenyloxy; a lower alkylthio; a lower haloalkylthio; --Si(CH₃)₃ ; --OH; --N(CH₃)₂ ; --SCN; --COOCH₃ ; or --OCH(CH₃)COOC₂ H₅, and n denotes an integer of 1 to 5, said R³ being the same or different when n is an integer of 2 to
 5. 13. A 3(2H)-pyridazinone derivative according to claim 12 wherein, R denotes tert.-butyl R¹ and R² denote each independently hydrogen or methyl, R⁴ denotes a halogen, R³ denotes a halogen, a straight or branched C₁ to C₁₂ alkyl, a cycloalkyl unsubstituted or substituted by a lower alkyl; a straight or branched C₁ to C₈ alkoxy; a lower haloalkyl; a lower haloalkoxy; ##STR198## (wherein X denotes a halogen, a lower alkyl, a lower alkoxy, a lower haloalkyl, a lower haloalkoxy, --CN or --NO₂, and m denotes 0 or an integer of 1 to 5, said X being the same or different when m is an ineger of 2 to 5); a pyridyloxy which may be substituted by a halogen and/or --CF₃ ; a lower alkenyloxy; --Si(CH₃)₃ ; and n denotes an integer of 1 to 5, said R³ being the same or different when n is an integer of 2 to
 5. 14. A 3(2H)-pyridazinone derivative according to claim 1: wherein, R denotes tert.-butyl, R¹ and R² denote each independently hydrogen or methyl, R⁴ denotes a halogen, R³ denotes a straight or branched C₁ to C₆ alkyl, a cycloalkyl unsubstituted or substituted by a lower alkyl; a straight or branched C₁ to C₆ alkoxy; a lower haloalkyl; a lower haloalkoxy; ##STR199## wherein X denotes a halogen, a lower haloalkyl, a lower haloalkoxy, and m denotes 0 or an integer of 1 to 3, said X being the same or different when m is an integer of 2 to 3; a lower alkenyloxy; --Si(CH₃)₃ ; and n denotes an integer of 1 to 3, said R³ being the same or different when n is an integer of 2 to
 3. 15. A method of killing a target organism selected from the group consisting of insects, acarids, nematodes and fungi, said method comprising contacting the target organism with an effective amount of a compound of the formula: ##STR200## wherein R¹ and R² denote each independently hydrogen or lower alkyl; R³ denotes a halogen; a straight or branched C₁ to C₁₂ alkyl; a cycloalkyl unsubstituted or substituted by a lower alkyl; a straight or branched C₁ to C₁₂ alkoxy; a lower haloalkyl; a lower haloalkoxy; ##STR201## (wherein X denotes a halogen, a lower alkyl, a cycloalkyl, a lower alkoxy, a lower haloalkyl, a lower haloalkoxy, --CN or --NO₂ and m denotes 0 or an integer of 1 to 5, said X being the same or different when m is an integer of 2 to 5); a pyridyloxy which may be substituted by a halogen and/or --CF₃ ; a quinoxalyloxy which may be substituted by a halogen and/or --CF₃ ; a lower alkenyloxy; a lower alkylthio; a lower haloalkylthio; --Si(CH₃)₃ ; --OH; --N(CH₃)₂ ; --SCN; --COOCH₃ ; or --OCH(CH₃ (COOC₂ H₅, and n denotes an integer of 1 to 5, said R³ being the same or different when n is an integer of 2 to
 5. 16. 2-tert.-butyl-4-chloro-5-(4-n-propoxybenzylthio)-3(2H)-pyridazinone of the formula ##STR202## 